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Jamie MacMahan

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Video measurements of runup were collected at low tide along several profiles covering an alongshore distance of 500 m. The morphology displayed a complex shape with a shoreline sandwave in the lower beach face of about 250 m long mirrored in the inner sandbar. Wave conditions were stationary and moderate (offshore height of 2 m and peak period of nearly 13 s) but yet dissipative. Runup energy was dominated by infragravity frequencies. Alongshore variations in runup (by a factor up to 3) observed both in the incident and infragravity bands were much higher than reported previously (e.g., Guedes et al., 2012, https://doi.org/10.1016/j.csr.2012.08.022; Ruggiero et al., 2004, https://doi.org/10.1029/2003JC002160) while...
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A process-based numerical model of the mouth of the Columbia River (MCR) and estuary, Oregon and Washington, was applied to simulate hydrodynamic conditions for the time period of the Office of Naval Research-funded River and Inlets Dynamics (RIVET II) experiment between May 9 and June 15, 2013. The model application was constructed using Delft3D, an open-source software package used to solve the unsteady shallow water equations to simulate water motion due to tides, waves, wind, and buoyancy effects (Lesser and others, 2004). This portion of the USGS data release describes the model application for this experiment and presents input files necessary to run the Delft3D model. Model Description The model application...
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This portion of the data release contains Lagrangian drifter data collected in the Mouth of the Columbia River (MCR), Oregon and Washington, in 2013. Lagrangian surface currents were measured using drifters equipped with global navigation satellite system (GNSS) receivers. A total of eight drifter deployments were performed between May 25 and June 8, 2013 (USGS Field Activity S-03-13-WO; Table 1). For each deployment, drifters were released within the MCR and their positions were recorded until the drifters were recovered. The average duration of the drifter deployments varied between 1.6 hr and 17.2 hr, and the number of drifters released in a deployment ranged between 11 and 84. The initial positions and timing...
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This portion of the USGS data release presents sediment grain-size data from samples collected from the mouth of the Columbia River, Oregon and Washington, in 2013 (USGS Field Activity Number S-03-13-PS). Surface sediment was sampled using a small ponar, or 'grab', sampler on May 9, 2013 from the F/V Cape Windy at three locations corresponding to sites where instrumented tripods were deployed. A handheld GNSS receiver was used to determine the locations of sediment samples. The grain-size distributions of samples were determined in the USGS Pacific Coastal and Marine Science Center sediment lab. Approximately 20 g of sediment was sub-sampled and 10 mL of 35 percent hydrogen peroxide was added to remove organic...
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During May and June of 2013, the U.S. Geological Survey in collaboration with Naval Post-Graduate School, the University of Miami, and Deltares USA, participated in the Office of Naval Research-funded River and Inlets Dynamics (RIVET II) experiment to investigate the hydrodynamics of the mouth of the Columbia River (MCR). The field experiment consisted of the collection of continuous oceanographic data at three moorings, shipboard surveys and Lagrangian drifter deployments to characterize spatial variability in hydrodynamics and water properties, and hydrographic surveys to characterize seafloor morphology in the MCR. These datasets were used to calibrate and validate a hydrodynamic model of the MCR, estuary, and...
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